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techknight

Designing a portable RAM card

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Yeah I had forgotten that.. duhh.. 1mb on board.. :) Could make it a 9MB I suppose.. but will only work on 5120 like that no?? Did u want me to send it to you so you can take a peek at it?? 

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It does make me wonder why they didn't popular that last set of pads. Maybe they just thought 9 MB was a strange number?

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Well I did screw up. on one thing...

 

The boards did ship, and they shipped DHL. Unfortunately, they uncovered some big scandal at the ShenZhen dock, which is where my package is stuck at. 

 

Something about counterfeit money and other stuffs, causing packages to be delayed up to a month or so before it leaves the dock via DHL. 

 

I wish i would have known this prior to ordering and shipping via DHL... 

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Doh! Bummer. With luck they'll get it sorted out quickly. They can't want to lose a bunch of commerce because of delays. Some time last year there was a big obstacle in shipping for remote control toy companies. Something about shipping lithium-poly batteries. They got it figured out eventually, but it took a while.

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Well, if this delays it too long, can you cancel your order and redo it via another carrier?

 

If the company from which you got these is reasonable, they should be able to do that for you.

 

In an ideal world, anyway....

 

c

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That looks a bit awesome - well done.  Might be keen for one provided my non-backlit Portable decides to function again.

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Does it work?

 

it isn't fully assembled yet. I have to wait on the rest of the parts, had to replenish the project fund bucket which the circuit board order emptied. 

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Nice Techknight!!!!!!!!!!!!!! Looks great!!!!!!!! Again I can't even wait... my orders will be in as soon as it's ready.. I am sure many others will have their orders in as well.. :)

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Finally! Sheesh...... Was getting worried as it kept showing delivery status not updated on USPS. 

 

But its good, they came. 

 

Got some finished pictures below. any thoughts so far? All that basically has to be done now is the CPLD jtagged and then tested!

 

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post-366-0-19021400-1415061045_thumb.jpg

post-366-0-94302200-1415061085_thumb.jpg

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Flashed it. Almost worked first try.

 

Passes no sad macs. 

 

But something is wrong in my CPLD code I think. it bombs with memory manager error when I go to about the finder. 

 

or if i do a get info on anything, itll crash with address error.... 

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I'm impressed you got that far on the first try. If you'd actually gotten it 100% off the bat I would have needed to say something about the devil and selling of souls...

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I did some more work on the CPLD code. 

 

I removed all decoding logic except the very basic stuff, hooking up only the lower half of the first chip to the 4-to-16 decoder. 

 

Tried it again, boom 2MB. 

 

So... at least i know my board configuration is good! I didnt have any doubts about that. :p At least I got the hardware perfect right off the bat. 

Edited by techknight

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Adding one select line at a time, added bank switching A20 line. 

 

Now I am seeing up to 5MB so far, NICE... I will keep doing this for each 1MB block at a time until I figure out where my issue was. 

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